Metered dose inhalers for delivering aerosol medication for inhalation by a user are disclosed in U.S. Pat. Nos. 5,487,378; 5,522,378; 5,622,162; 5,794,612; 5,839,430; 5,894,841; and 6,152,130. Commonly owned U.S. Pat. Nos. 5,743,251 and 6,234,167 disclose aerosol generators that vaporize a liquid formulation to form an inhalation aerosol.
Other techniques are known for generating aerosols. For example, U.S. Pat. Nos. 4,811,731 and 4,627,432 disclose devices for administering medicaments to patients in which a capsule is pierced by a pin to release a medicament in powder form.